Foundry researchers have coupled graphene, a monolayer form of carbon, with thin layers of magnetic materials like cobalt and nickel to produce exotic behavior in electrons that could be useful for next-generation computing applications.
The work was performed in collaboration with French scientists including Nobel Laureate Albert Fert, an emeritus professor at Paris-Sud University and scientific director for a research laboratory in France. Fert shared the Nobel Prize in Physics in 2007 for his work in understanding a magnetic effect in multilayer materials that led to new technology for reading data in hard drives, for example, and gave rise to a new field studying how to exploit and control a fundamental property known as “spin” in electrons to drive a new type of low-energy, high-speed computer memory and logic technology known as spintronics.
In this latest work, the research team showed how that spin property – analogous to a compass needle that can be tuned to face either north or south – is affected by the interaction of graphene with the magnetic layers.
The researchers found that the material’s electronic and magnetic properties create tiny swirling patterns where the layers meet, and this effect gives scientists hope for controlling the direction of these swirls and tapping this effect for a form of spintronics applications known as “spin-orbitronics” in ultrathin materials. The ultimate goal is to quickly and efficiently store and manipulate data at very small scales, and without the heat buildup that is a common hiccup for miniaturizing computing devices.
Typically, researchers working to produce this behavior for electrons in materials have coupled heavy and expensive metals like platinum and tantalum with magnetic materials to achieve such effects, but graphene offers a potentially revolutionary alternative since it is ultrathin, lightweight, has very high electrical conductivity, and can also serve as a protective layer for corrosion-prone magnetic materials.
The latest research represents an early step toward this goal, and a next step is to control nanoscale magnetic features, called skyrmions, which can exhibit a property known as chirality that makes them swirl in either a clockwise or counterclockwise direction.
